It looks kinda like they had to remove that part in order to give clearance to the clutch components right there...

The funny thing is that there is a pic around here somewhere, I think in the thread about changing out the cam chain, where the cam shaft looks like it had a chunk missing too. What kind of manufacturing practices are they using? Instead of a a machine, we're going to use TNT to remove that little piece....

As long as it rides good, I don't care

I have to say I was at first shocked when I saw the pictures of the camshafts with the "piece" missing...
I was about ready to loose my cool over it when I found out it had been done intentionally to aid in oiling of the camshaft to "rocker arm" (or whatever it's called) interface.